"Your skills rely upon enhancing natural healing processes and have no noticeable effect on the short term - you are, however, skilled at making sure wounds are properly dressed to reduce risk of infection or further complications."
So in other words, having an occupation of Healer or Herbalist does nothing to help with healing in game terms?
No. No other words - just the ones I used, if you please.
Long term recovery, such as spending days resting to trigger the normal HP recovery, can be enhanced by a healer or herbalist with the right supplies. Probably as far up as 150% healing rate (3 hp per 2 days rest).
I also use infection when it seems particularly high-risk (character's trudging through swamp-land and never stopping to treat their wounds), and allow healer or herbalist characters ability to treat and prevent that.
A healer, not an herbalist, would also be useful in mitigating the effects of certain critical hit results such as broken limbs - anything a splint or good bandage would reduce the detriment of.
Far from useless, just as I originally said.